Rob, I have seen the small and large dataset concept discussed since the early days of DFSMS. To tell the truth I have never seen the benefit of doing this.
It has been suggested that it helps reduce allocation failures by reducing fragmentation, but having always worked in shops with ACC/SRS or similar I was pretty aggressive with the rules and did not have a problem even when I ran development STORGRUPs up to 5% free space. And I never defragged. If fragmentation is the reason for sized based pools, then I wonder if the practice is still necessary. DFSMS has implemented some elements of ACC/SRS to reduce allocation problems, and if you are using 3390-A with Cylinder allocation areas you have a natural separation of small and large datasets within the volume. I would say do not implement size related pools, but rather make sure you make best use of allocation recovery in DFSMSdfp, ACC/SRS, PRO-SMS, or whatever ISV software you have as part of your implementation. Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] > On Behalf Of Rob Schramm > Sent: Thursday, July 05, 2012 8:01 AM > To: IBM-MAIN@LISTSERV.UA.EDU > Subject: Re: [IBM-MAIN] Converting to SMS for the first time > > You may want to consider the use of a couple size-related pools. During one > analysis ... something like 80% of the data sets were below 5 tracks. > > > Rob Schramm > Senior Systems Consultant > Imperium Group > > > > On Thu, Jul 5, 2012 at 10:52 AM, Elardus Engelbrecht < > elardus.engelbre...@sita.co.za> wrote: > > > Ron Hawkins wrote: > > > > >I would urge you to consider vertical pooling rather than horizontal > > pooling. > > ... > > > My key point is to go horizontal, and avoid vertical pooling. > > > > Vertical against horizontal? Perhaps I missed something in your post, > > but in my very humble opinion, I think both sentences are not speaking > > the same tongue.... > > > > Of course, I'm pretty sure I'm as usual wrong. Please correct me if > > needed ... > > > > Many thanks and have a terrific day! > > > > Groete / Greetings > > Elardus Engelbrecht > > > > ---------------------------------------------------------------------- > > For IBM-MAIN subscribe / signoff / archive access instructions, send > > email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > > > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, send email to > lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
